Checking Your Brakes

What are They?

The brakes are mechanisms that allow you to control the forward speed of your bike.

What do they Do?

They slow the spin of your forward-moving wheels by clamping brake pads onto the smooth sidewalls of your wheel rims.

General Brake Information

Your brakes are without a doubt one of the most important parts of your bike. They must be clean, in good condition, and properly adjusted before every ride.

Braking systems are designed to respond quickly and efficiently to your commands. To do this, they are designed with exacting clearances. Over time and in response to wear, brake systems often lose some of their "tightness". This leads to longer response times, less efficient braking and less bike control.

What Needs To Be Checked?

• Brake levers: Your levers can get gummed up with grime and dirt over time. They can also slip out of position on your handlebars.
• Brake pads: Pads wear down over time in response to normal use. This can lead to slower brake response times, and it can require more effort from you to engage your brakes. Pads can also be jarred out of position.
• Brake assemblies: Brake assemblies include the brake arms, the brake shoes (which hold the brake pads in place) and the pads themselves. These assemblies can be installed incorrectly or get jarred out of proper position as a result of aggressive riding, accidents or crashes. They should be checked to make sure that all component parts move freely and are properly positioned.

  NOTE: Many apparent brake assembly problems are actually caused by wheels that are damaged or out of true. If you develop persistent braking problems, take your bike to a full-service REI bike shop and have your wheels checked.

• Brake cables and housings: Cables can fray, rust and/or weaken over time. When this happens, the extra slack in the system can cause your brake pads to set up a little further away from your wheel rims than before. Cables can also wear, kink, and fray as a result of normal use. The flexible cable housings which protect your brake cables can break, corrode clog up or fray over time.

How Often Should I Check?

Give your brakes an overall check before every ride. Make sure your brake components are properly positioned and in good working order.

In addition to this, have your brakes inspected and serviced regularly by an experienced mechanic to catch problems that you may not be experienced enough to spot and/or fix. Every 6 months or so should be fine for occasional cyclists. Take your bike in more often if you ride hard and/or frequently.

Brake Check Procedures

• To check your brake levers: simply squeeze them. When your levers are fully engaged, there should be approximately one inch of space between the inside edge of each lever and your handlebars. Your brakes should hold solidly against your leaning weight. The levers should be mounted firmly on your handlebars (test each brake lever separately, by pushing up, down and laterally) and they should move smoothly when squeezed, without jerking or squeaking.
• To check the condition of brake pads: check to see if your pads are glazed, cracked, or significantly worn. Glazed pads can be cleaned using the procedures listed below. Pads that are cracked or worn down significantly (many have slots cut into them to help gauge how far down they've been worn) should be replaced. Unevenly worn pads should either be sanded flat or replaced.
• To check the position of your brake assemblies: visually inspect both the front and the rear systems and make sure they're centered around each wheel with the brake pads equidistant from the two rim surfaces. Each pad should:
  • Make contact fully with the rim when the brake is engaged (without touching the tire above or hanging over the lower edge of the rim).
  • Be "toed-in" slightly when viewed from above, so that the leading edge of the pad makes contact with the rim surface slightly before the back edge does.
• To inspect the brake cables: check them for visible frays, rust, or signs of wear during all major brake overhauls and maintenance checks. Cables should move freely through all cable housings and the guides that hold them in place.

Common Brake Problems and Solutions

NOTE: Basic brake system maintenance involves making sure that brake components are properly positioned and in good working order. Full brake "adjustments" are beyond the scope of this introductory clinic, and are not described here.

• Incorrectly functioning brake levers

  Brake levers typically malfunction for one of three reasons:

  1. The braking system is not fully hooked up or "engaged"
  2. The levers themselves are damaged or dirty
  3. The brake pads are not close enough to the rims

  Solution A: Most modern braking systems have some sort of quick-release mechanism that allows you to loosen the cable system without throwing your brake system out of tune. This slack is typically needed to open the brake arms wide enough to get your wheel out from in between them.

  Some of these quick-releases are located on brake assemblies, others are located on brake levers or elsewhere along the cable route. If you find too much slack in your braking system, check these quick-release mechanisms first to make sure they are engaged.

  Solution B: If your brake quick-releases are connected properly but the brake levers still function poorly (or not at all), the levers themselves may need cleaning or repair. Follow the cleaning procedures described in the following section.

  Solution C: If solutions A and B don't fix your brake lever problem, your brake pads may not be close enough to your wheel rims to start with. Before you reposition them, however, check to make sure that the pads are not worn down too far (if they are, they should be replaced). If your brake pads are okay, turn the cable adjustment knob (located where your brake cables enters your levers or at the brake caliper on road bikes) counterclockwise until the desired pad/rim distance is achieved (1/8th of an inch is standard). If the cable adjustment knob (also known as the barrel adjustment) bottoms out before the pad is in position, you may have to bring your bike into an REI bike shop for a more complete brake adjustment.

  HINT: Whenever you bring your bike in for brake service, ask the mechanic to check your wheel rims as well. Your rims are an integral part of your braking system. Damaged or improperly trued rims/wheels can cause or contribute to braking problems.

• Incorrectly positioned brake assemblies/brake pads

  Incorrectly positioned brake assemblies can cause ineffective braking and/or brake squeaking.

  Solution: Brake pads and brake assemblies are usually held in place by simple systems of binder bolts, washers and mounting nuts. Re-adjustment in most cases involves little more than loosening the appropriate nut or bolt, maneuvering the assembly into the proper position, and tightening the binder bolt again to keep the component in place.

  Because of the large number of brake designs available, detailed descriptions of specific adjustments are not included here. Take some time to familiarize yourself with your brake assemblies and how they're put together, so you can make basic adjustments if necessary.

• Improperly gripping brakes

  If your brakes still grip poorly after you've checked your levers and assemblies, your brake system may need professional adjustment. But before taking the bicycle to a shop, check for the following:

  • Dirty rims: Dirty wheel rims can cause poor braking performance, even if your brakes are working properly. Solution - Check your rims, and clean them if necessary.
  • Worn or "glazed" pads: Rim grime, general brake use and time can all cause your brake pads to become hard, slick, and ineffective. Solution - Check your pad surfaces whenever braking performance drops or your brakes become "squeaky". Glazed or hardened pad surfaces should either be cleaned (as described below) or replaced.

Brake Cleaning Procedures

You should clean your brake system any time performance drops or a pre-ride inspection uncovers dirt or grime in the system. Frequent cleaning is especially important for your brake pads.

• Brake pads: Clean grime and residue off your brake pads using a rag and alcohol (first choice), sand paper or a Scotchbrite pad. Brake pad surfaces should be soft enough that you can scratch them with your fingernail. Carefully pry out any foreign objects found embedded in the pads.
• Brake cables: Wipe down and lightly lubricate your brake cables every few months (or whenever signs of grime and/or rust appear on their visible surfaces). Lubricate by applying a small amount of bike oil to the cable near the cable guides and housings. Be careful not to get any lubricant on your brake pads or wheel rims.
• Brake arm and lever pivots: The various pivot points found throughout your brake system can be maintained by wiping them clean frequently (as often as every ride), and by applying a very small amount of lubricating oil to the pivot areas while moving them back and forth.